Along with increase in data amount, distributed processing such as grid computing is drawing attentions. An application example of distributed processing is a calculation of total sales. It is assumed here that the total sales amount is calculated by adding all transaction amounts that are registered as transaction data. If the transactional amount is small, a single computer may complete the calculation within a short time. If the transactional amount is large, it may take a long time to calculate the total sales amount. In that case, it is possible to acquire the calculation result within short time by distributing the transaction data into multiple computers and by executing the calculation in a distributed manner on each of the computer.
Patent Literature 1 listed below describes a technique related to distributed computing technique. The technical problem of Patent Literature 1 is “To provide an access securing security to a resource in a distributed computer network”. The solution to the problem of Patent Literature 1 is “This device includes a job ticket service 60 capable of storing a job ticket 61, in which the job ticket provides reference to a job, the job includes one or more resources, and a processor 80 accesses to the job ticket to execute the job, an authentication mechanism 94 capable of verifying the identification of a process trying to access to the job ticket, and an authorization mechanism 92 capable of receiving the identification from the authentication mechanism and providing authorization for accessing to the job ticket to the processor, wherein when the processor accesses to the job ticket, it accesses to one or more resources.” (refer to Abstract).
Patent Literature 2 listed below describes a technique that controls accesses to data files located on networks. The technical problem of Patent Literature 2 is “To provide a technique that controls, when detecting a file operation on a terminal connected to a network, the operation by determining whether the operation is authorized”. The solution to the problem of Patent Literature 2 is “An operation information acquirer 21 of a server S acquires operation information from a terminal C. An authorization requester 22 specifies an authorizer according to the acquired operation information, acquires authorizer information, and sends an authorization request to the specified authorizer. An authorization result receiver 23 receives authorization results from each authorizer, and passes the authorization results to an aggregator 24. The aggregator 24 acquires the authorizer information and the authorization result, and generates an aggregation result when a predetermined condition is satisfied. An authorization determinator 25 acquires the aggregation result from the aggregator 24, and determines whether or not to authorize according to the operation information and the aggregation result. A controller 26 executes a predetermined control according to the determination result by the authorization determinator 25.” (refer to Abstract).